Coupler for road slabs



Nov. T18, i941. R. R. ROBERTSQN @9233?@59 COUPLER FOR ROAD SLABS Filed July 1945 un@ I f Patented Nov. 1,8, 1941 UNITED STATES PATENT OFFICE 2,262,859 f T j coUPLER Foa ROAD SLABs i Robert R. Robertson, Chicago, Ill.

Application July 10, 1940, Serial No. 344,630-` 4 Claims.

concrete road structure by adding road lanesadjacent previously formed road lanes by the use of improved couplers consisting of anchor hooks connected by knuckle joints permitting pivotal movement between the anchor hooks and thereby allowing slight adjustments oi adjacent road slabs or lanes with respect to one another without permitting dislocation of adjacent road slabs or lanes with respect to one another.

It is an object of this invention to provide improved coupling units to facilitate the addition of an adjacent road slab or road laneto a previously formed slab or lane by the use of anchoring hooks with adjustable knuckles embedded in the old slab or lane with the knuckles accessible through the side of a slab or lane to permit the engagement of additional anchoring hooks with the knuckles whereby the additional hooks may eventually be embedded in the new concrete poured to form an adjacent slab or road lane.

1t is furthermore an object of this invention to provide a road widening mechanism including a channel member embedded in the side of a concrete road lane and housing a plurality of spaced joint knuckles movably engaged on projecting portions of anchoring members embedded in the road lane to form an arrangement whereby additional anchoring hooks may be engaged in the joint knuckles and then be embedded n concrete forming an adjacent road lane so that the additional road widening lane may be coupled to the old road lane and allowing relative movement between the old and new lanes and between the anchoring hooks of the couplers and obviating cracking of the road slab material around the couplers which usually occurs when adjacent road lanes are connected by rigid dowel bars or coupling means.

Another object of the invention is the provision of an improved and simplied form of a road slab coupler consisting of anchoring members for embedding in adjacent slabs and connected to one another by a nut knuckle.

Another object of the invention is the provision of a simplified form of connecting unit consisting of hook members one of which has a combination nut and knuckle pivotally engaged thereon to permit the remaining hook member to be removably engaged with the nut portion of the connector to permit pivotal adjustment of the connected hook members.

It is an important object of this invention to provide a concrete road widening mechanism including a removable road form, a groove forming channel member and a plurality of adjustable couplers each including hook members pivotally connected one to the other by means of a combination knuckle and nut pivotally engaged on one of the hook members within the channel member and accessible when the road form is removed to permit the other hook member to be .engaged in the combination knuckle and nut member.

Other and further important objects of this invention will be apparent from the disclosures in the specication kand the accompanying drawing. y

The invention (in a preferred form) is illustrated in the drawing and hereinafter more fully described. i

In the drawing:

Figure 1 is a fragmentary isometric View of a concrete road widening mechanism including improved adjustable couplers embodying principles of this invention.

Figure 2 is an enlarged fragmentary vertical detail section through a concrete road showing the road form still in position with the major portion of a joint coupler embedded in the road slab and showing the position of the remaining hook portion of the coupler in dotted lines to indicate the location of said portion when the road form is removed.

Figure 3 is a fragmentary detail section taken on line III--III of Figure 2 with the concrete and the road form omitted. i

Figure 4 is a reduced vertical detail Asection through a concrete road showingvadjacent road slabs or lanes connected to one another by means of an improved coupler partly shown in section and partly in elevation.

Figure 5 is an enlarged top plan View of the coupler knuckle.

Figure 6 is a bottom plan View of the coupler knuckle.

Figure 7 is a perspective view of a modified form of a coupler knuckle.

As shown in the drawing:

In the construction of concretehighways and the like it has been the practice to start .the construction by either laying two adjacent lanes simultaneously, or rst constructing one lane'and then adding additional lanes either on lone side or both sides of the previously constructed lane. It often becomes necessary to add additional lanes to either one or both sides of old roads'.

and are flexed by the road slab shifting tendenciesl to cause damageto the concrete.

'Ihe present invention relatesV to mechanisms for facilitating road widening or slab additions'm-` to be made in concrete structures by the use of improved knuckle type couplers embracingseparable members adapted to be convenientlyassembled for anchoring in adjacent road slabs or road lanes at the same or at diiferent times lde- 'f pending upon when the adjacent are constructed.

In the present, embodiment of this invention the reference numeral Iindicates a road subgrade upon which adjacent road slabs or road are-formed at different times. If

slabs or lanes lanes 2=and3 desired the road-lanes 2 and 3 may be separated by a filler or Lseparating strip 4 constructed of plasticy or anyother suitable material for sepy arating adjacent faces of adjoining slabs or lanes.v

It is the. intention of this invention to provide a, mechanism for conveniently widening a concrete. structure such, for example, as a road; to permit additional slabs or lanes to be added to Y previously formed slabs or lanes. 'Ihe improved road Awidening mechanism `embraces a road form constructed of metal or other suitable material and bri'ey comprising a base flange 5 and arlintegral upright flange 6 adapted to vbe seated von the roadsub-grade previous to concrete to form the road slab or lane 2. The road forms are usually used in pairs with the forms positioned on opposite sides of a road bed orsub-grade to define thev width slabv or lane which is to be constructed.

' In order to take vcare of'vroadwidening at future dates and provide. arrangements whereby additional road slabs or` lanes may be constructed Aof a concretev the pouring of adjacent the old slabs or lanes and properly con- Y nected thereto, a groove forming channel shield or sheet metalV channel member` 1 is releasably clamped longitudinally against the outer surface of the vertical flange 6 of the road form by any suitable clamping means temporarily holding the channel member in place `during the pouring of concretef The channel member 1 has the base wall thereof providedwith a `pluralityof spaced Aslots or openings 8 through which portions of imvproved road. slab couplers are engaged.

' When a road slablorfroad lane 2 is formed so that another .road slab or lane may be connected adjacent thereto at a later date, the groove forming channel member, 1 for the lane 2 is equipped withthe primary portions of improved couplers so that secondary. portions of the couplers ma be connected thereto at a subsequent time.l i

Each of the improved couplers forming a part of the road widening mechanism,- comprises an open link or double ,hook .anchoring member 9 constructed of a steel or iron `rod themendsof f which are bent to forman anchoring,4 hookat one end and a supportingrhook at the opposite Vend'.Y The anchoring hook4 en d of theanchoring link'9 'is projected through one of the openings 8in the channel member 1.A Pivotally. engaged on the/supporting hook end of the anchoring'link is' a knuckle (or connectingfmernbercomprising `a vthe road form, a plurality throughwhich the supporting hook end of the anchoring link 9 is adapted to be engaged as clearly illustrated in Figure 3. To complete the coupler an anchoring hook I4 has the threaded end I5 thereof threaded into the opening I3 of the nut I2.

Before the concrete slab or lane 2 is formed and before thechannel member 1 is engaged against of coupler anchoring links 9 are projected through the openings 8 in the channel member 1 until the knuckles Ill are seated in the channel ymember 1 as illustrated in Figure 2. The knuckles I0 are shaped complementally to vtheI shape of the interior cross section of the groove forming channel memberr1 so that the knuckles may rock in the channel member. `With the anchoring members 9 and the knuckles supported thereon engaged with the groove forming channel member 1'.,v said channel' member may be pla-ced against the flange 6 ofthe road forni by any suitable removable l clamping means, thereby permitting concrete to be pouredV to form the road slab or lane 2 to embed the major portions of the anchoring members 9 and the channel member 1. After the formation of the slab 2 the road form exposing the open side 1 to permit access tobe Y and the nut portions I2 forming a part thereof.

When it is desired to add an adjacent road slab 3 and connect the saine to the road slab 2 for widening the road or concrete ystructure being formed, it is only 4necessary to'position the compressible ller strip 4 against the side of the slab 2 and then engage the secondary anchoring hooks I4 Athrough the threaded ends of the of the channel member had to the knuckles Il) I3 of the nut members vI2 of the knuckles seated thechannel member 1 of the previouslyV formed road section( Attention is called to the fact that with the secondary anchoring members I4 engaging inY the nut members I2, the knuckles Ill may be pivoted or rocked either transversely or longitudinally in the channel member 1 and on the supporting hook ends of the primary anchor-` ing members 9, thereby allowing relative longitudinal as Well as transverse shifting of the road slabs with respect to one another. With the secondary anehoring members Ill-connected with the knuckles seated inthe channel member 1 of the previously formed road section 2, the concrete for forming the additional road widening Vsection 3 is poured to embed the secondary anchoring members and to enclosethe filler strip .4 between the road slabs 2 and 3 as illustrated in Figure 4. While the coupler is described as kconsisting of ,a knuckle to which the anchoring members are connected to permit pivotal movement of the kllllCkle may be threaded therethroughl into lo'ck ing engagement with the other anchoring member knuckle together to form a arrangement permits the anehoringmember,

may be removed thereby filler strip 4 with the l anchoring members y I4 l.

i threaded into the openings at spaced rintervals in threaded into the unit, to be held in place during the pouring of concrete, Without requiring a separate support.

Figure 7 illustrates a modiiied form of coupler knuckle of unitary or one-piece construction and comprising a nut base portion I6 provided with a threaded opening I1 and With a longitudinally disposed passage I8. Integrally formed on the top of the nut portion I6 is a loop-shaped or arched head I9 to permit the knuckle to be engaged on the supporting hook end of an anchoring link or member 9 similar to the arrangement illustrated in Figure 3.

While the improved shiftable or adjustable coupler is illustrated and described in connection with a concrete ro-ad Widening mechanism in cooperation with a groove forming channel member, it Will of course be understood that the flexible knuckle type of coupler may be adapted for various other purposes.

It will furthermore be understood that various details of construction may be varied through a Wide range Without departing from the principles of this invention, Iand it is, therefore, not the purpose to limit the patent granted hereon other- Wise than necessitated by the scope of the appended claims.

I claim as my invention:

1, A coupling unit comprising a knuckle consisting of a nut portion having a threaded opening therein and an arched portion connected with the nut portion, an anchoring member hooked through the arched portion of the knuckle and pivotally adjustable with respect thereto, and a threaded anchoring member threaded into the nut portion of the knuckle and movable therewith with respect to the first anchoring member, said second anchoring member adapted to be threaded through the nut portion o the knuckle into engagement With the rst anchoring member to lock the anchoring members arrd the knuckle together to form a rigid construction.

2. A road Widening mechanism including in combination a groove forming member for temporary engagement against a road form, said groove forming member having spaced slots therein, knuckle members loosely seated in spaced relationship in the groove forming member adjacent the slots, and anchoring members projecting through the slots of the groove forming member and pivotally connected with the knuckle members to hold the knuckle members in position for receiving additional anchoring members when it is desired to Widen the road.

3. A concrete road Widening mechanism including in combination a groove forming member having a row oi spaced slots in the longitudinal centerline thereof, a plurality of knuckles having openings therethrough, said knuckles movably seated in the groove forming member adjacent the slots therein, primary anchoring members projecting through the slots in the groove forming member and pivotally engaged through the openings in the knuckles, and secondary anchoring members engaged with the knuckles and pivotally movable therewith with respect to the primary anchoring members.

4. A road Widening mechanism including in combination a slotted groove forming channel member, a knuckle movably seated therein and having a passage therethrough, a nut portion in the knuckle, an anchoring member projecting into` the slotted channel member and movably engaged through the passage in the knuckle, and a second anchoring member releasably engaged with the nut portion oi the knuckle.

ROBERT R. ROBERTSON. 

